<md-menu >
  <md-button aria-label="Options" class="md-icon-button" style="width: 120px;" ng-click="openMenu($mdOpenMenu, $event)">
    <ng-md-icon icon="person"></ng-md-icon> {{username}}  <ng-md-icon icon="expand_more"></ng-md-icon>
  </md-button>
  <md-menu-content width="3">
    <md-menu-item>
      <header> <ng-md-icon icon="account_circle"></ng-md-icon>{{username}}</header>
    </md-menu-item>
    <md-menu-item>
      <md-button ng-click="logout()">退出</md-button>
    </md-menu-item>
    <md-menu-divider></md-menu-divider>
    <md-menu-item layout="column">
      <md-button ng-click="aboutKylo()" md-prevent-menu-close="md-prevent-menu-close">
        <span style="float:left;">关于我们</span>
      </md-button>
    </md-menu-item>
  </md-menu-content>

    <md-button style="width: 25px;min-width:40px"  ng-click="logout()">退出

    </md-button>

</md-menu>
